双极器件ELDRS效应研究进展

电离总剂量是航天电子系统辐射效应研究的重要问题,其中双极器件因其特有的低剂量率损伤增强（Enhanced low Dose Rate Sensitivity,ELDRS）效应,已成为航天用双极器件抗电离总剂量效应发展重点突破的方向及难点问题。本文综述了ELDRS效应及低剂量率加速评估技术的研究进展,并结合ELDRS效应难点问题,给出了最新关于ELDRS效应的研究结果。试验结果表明,采用变温辐照方法不仅可以保守地用于双极器件在0~200 krad （Si）范围的ELDRS效应评估,将评估时间从7.7个月缩短至11 h,还可将其应用于双极模拟电路总剂量和单粒子协同效应的评估,同样可以获得保守且快速的评估效果。     

Synergistic effect of total ionizing dose on single event effect induced by pulsed laser microbeam on SiGe heterojunction bipolar transistor

The synergistic effect of total ionizing dose(TID) on single event effect(SEE) in SiGe heterojunction bipolar transistor(HBT) is investigated in a series of experiments. The SiGe HBTs after being exposed to 60 Co g irradiation are struck by pulsed laser to simulate SEE. The SEE transient currents and collected charges of the un-irradiated device are compared with those of the devices which are irradiated at high and low dose rate with various biases. The results show that the SEE damage to un-irradiated device is more serious than that to irradiated SiGe HBT at a low applied voltage of laser test. In addition, the g irradiations at forward and all-grounded bias have an obvious influence on SEE in the SiGe HBT, but the synergistic effect after cutting off the g irradiation is not significant. The influence of positive oxide-trap charges induced by TID on the distortion of electric field in SEE is the major factor of the synergistic effect. Moreover, the recombination of interface traps also plays a role in charge collection.     

双极电压比较器电离辐射损伤及剂量率效应分析

为了对双极电压比较器在电离辐射环境下的损伤变化特征及其剂量率效应进行研究,选择一组器件,在不同偏置条件下进行60Coγ高低剂量率的辐照和退火试验.结果表明:电压比较器的电源电流、偏置电流及失调电压等多个关键参数都有不同程度的蜕变;偏置条件对于电压比较器的辐射响应有很大影响;此外,不同公司生产的同种型号电路表现出不同的剂量率效应;通过对测试结果分析,系统地讨论了各参数变化的原因,并结合电离损伤退火特性,探讨了各剂量率效应形成的机理.研究结果对工程应用考核提供了参考,而且为设计抗辐射加固器件提供了依据.     

重离子导致的锗硅异质结双极晶体管单粒子效应电荷收集三维数值模拟

针对国产锗硅异质结双极晶体管(SiGe HBTs), 采用半导体器件模拟工具, 建立SiGe HBT单粒子效应三维损伤模型, 研究影响SiGe HBT单粒子效应电荷收集的关键因素. 分析比较重离子在不同位置入射器件时, 各电极的电流变化和感生电荷收集情况, 确定SiGe HBT电荷收集的敏感区域. 结果表明, 集电极/衬底结内及附近区域为集电极和衬底收集电荷的敏感区域, 浅槽隔离内的区域为基极收集电荷的敏感区域, 发射极收集的电荷可以忽略. 此项工作的开展为下一步采用设计加固的方法提高器件的抗辐射性能打下了良好的基础. 关键词： 锗硅异质结双极晶体管 单粒子效应 电荷收集 三维数值仿真